U.S. Pat. No 1,982,560 issued in 1934 to the Rostone, Inc. corporation, discloses a clip system for both releasably interlocking a pair of superimposed concrete blocks as well as for releasably interlocking each given block to a vertical wall against which it is adapted to be applied. Three different embodiments of clips are envisioned to be used in this invention: clips 5, 7 and 8, as illustrated in FIGS. 5, 6 and 8 respectively of the drawings. Clip 5 defines a rectangular metal plate, having first and second long edges. Said first edge of each clip 5 is located outwardly relative to the wall 1, and defines a plurality of alternating, coplanar, upwardly and downwardly extending tongues 5b and 5c which extend orthogonally of the main body of the clip. Tongues 5b and 5c snugly engage into corresponding registering grooves b and c made on the bottom edge portion of an upper concrete block and on the top edge portion of an underlying lower concrete block, respectively. Therefore, relative horizontal play of the blocks is substantially prevented. Moreover, said second edge of each clip 5 defines an upturned elongated flange 5a, orthogonal to the main body of the clip 5. Flange 5a snugly engages into a pocket, under a wedge action behind a projecting ear 2 which is integral to the vertical wall 1, whereas horizontal motion of each block B relative to the wall 1 is substantially prevented. The generally cross-sectionally L-shape clip 7 is for use in securing the lowermost block B to the wall 1, as suggested in FIG. 7. Clip 8 is somewhat U-shape in cross-section, with a peg-like pointed leg on one side. It is further noted that the invention declares (column 2, lines 9-16) that he feels his invention is not limited to the use of such grooves b, c, in the concrete blocks and clips 5, 7 and 8, whereas other "interengaging devices" to secure the blocks in place are envisioned not to be excluded from the scope of this invention --an all-encompassing claim that would appear far-fetched.
Canadian patent No 911,193 issued in October 1972 to the German company Max Langensiepen Kom. Gesellschaft, as well as Canadian patent No 274,045 issued in 1927 to J. F. Makowski, both disclose a clip similar to clip 5 of the Rostone patent,supra.
U.S. Pat. No. 4,170,857 issued on 16 Oct. 1979 to the Austrian company Bauhu/ tte Leitl-Werke Rieger-Anlaggentechnik GmbH discloses a facade construction consisting of a number of superimposed blocks 2 and 3, which are interconnected to one another and to the supporting wall 8 by connecting means and applied against that upright wall 8. The connecting means includes: first vertical rods, 9, connected to the wall 8 by fasteners 9'; and second horizontal rods, 14, engaging complementary horizontal edgewise grooves 13, 13' in each pair of superimposed blocks 3 and being connected to the first rods 9. FIG. 3 suggests how the rods 9 and 14 would be interconnected. Moreover, there is shown in FIG. 7 an alternate block interconnecting means clip, defining a configuration having a first T-shape extension at one end and a second L-shape extension at the opposite end.
Canadian patent 1,057,928 issued on 10 Sep. 1979 to the United States Gypsum company, limited, further discloses in FIG. 3 a similar clip of H-shape.
Both U.S. Pat. No. 1,334,599 issued in 1920 to Wilfred CUSICK and U.S. Pat. No. 2,708,358 issued in 1955 to Carl SCHELS, show that it is well known to provide a building block with a downwardly projecting rib at its bottom outer edge, in order to outwardly overlap the upper edge of an underlying second block. Clearly, such overlapping ribs are directed at substantially preventing undesirable weathering of the edgewise joints between superimposed pairs of building blocks.
Canadian patent 1,057,928 discloses a clip for mounting a facing member spaced from a wall with the clip having upwardly and downwardly extending flanges which extend into recesses in the facing members.